A spacetime that is flat at infinity permits solutions where test particles in an otherwise empty universe possess inertia, violating Mach's demand that inertia vanish without surrounding matter.

?Rate how convincing each reason is below to see the overall strength.

No one has weighed in yet. Be the first to share reasons for or against this statement.

Ernst Mach(as the originator of the theory discussed): An Austrian physicist and philosopher (1838–1916) who argued that motion and forces only make sense when described relative to other objects, not relative to empty space itself.
Mach's principle (or Mach's demand)(as used in physics and philosophy of physics): A philosophy proposed by physicist Ernst Mach that says an object's inertia should only exist because of other matter in the universe, not on its own.
Spacetime(as one criterion for whether something is physically real): A physics concept combining space (location) and time into one continuous system—basically, every physical object exists somewhere at some moment in time.
Test particles(as used in physics): Imaginary tiny objects physicists use to explore how space and gravity work, small enough that they don't affect the system they're being tested in.

Based on where you are in your exploration